Hi Guys,
We are migrating AIX 5.1 to AIX 5.3. With this upgrade the C/C++ compiler is also upgraded to Visual Age C++ 6.0.
After upgrading, when we tried to (re)compile our programs (since ibm open library classes are not going to work with new compiler), we are getting so many errors with no clue how to solve. We are using the same make files which were working perfectly on AIX 5.1. The following errors are common for all programs.

"/usr/vacpp/inclue/iostream.h",line 114.38: 1540-0063 (S) the text "*" is unexpected.
"/usr/vacpp/include/iostream.h",line 300.25: 1540-0040 (S) the text "seekoff" is unexpected. "streampos" may be undeclared or ambiguous.
"/usr/vacpp/include/iostream.h",line 443.32: 1540-0600 (S) The reference to "ios" is ambiguous.
"/usr/vacpp/include/iostream.h",line 78.7: 1540-0425 (I) "ios" is defined on line 78 of "/usr/vacpp/include/iostream.h".
"/usr/vacpp/include/iosfwd", line 78.7: 1540-0425 (I) "std::ios" is defined on line 330 "/usr/vacpp/include/iosfwd".
"/usr/vacpp/include/iostream.h",line 692.32: 1540-0600 (S) The reference to "ios" is ambiguous.


This list goes on....
Can any one please have a look and let me know how can we solve this problem.

Thanks in advance.

What compiler options on the CLI are you using?

You can't use old-style include name like iostream.h, istring.h.
You must implements like this

#include <iostream>
#include <string>

and use corrects namespaces

using namespace std: // to use cout<<"text" << endl;

or use std::cout << "endl" << std::end;